#include <iostream>

using namespace std;
class A
{
public:
    virtual void f()
    {
        cout << "A::f()" << endl;
    }
};
class B : public A
{
private:
    virtual void f()
    {
        cout << "B::f()" << endl;
    }
};

int main()
{
    A* pa = (A*)new B;

    pa->f();
	return 0;
}